Composite sheets are manufactured by laminating a plurality of sheet materials using an adhesive: the sheet materials are selected from various plastic films, metal foils such as aluminum foils, metal deposited films, silica deposited films, and the like.
For the adhesive used for laminating composite sheets, a two component-type polyurethane adhesive in which a polyisocyanate component and a polyol component are mixed has been widely used, because of its superior adhesion performance.
As such a two component-type polyurethane adhesive, for example, there has been proposed a two component-curing laminating adhesive composition in which a polyol component is used as a main component, and a polyisocyanate component is used as a curing agent (for example, see Patent Document 1 below).
The composite sheets are used for outdoor sheets that are used under an outdoor environment, for example, leisure sheets, tents, plastic green houses, sheets for porch, rain coats, umbrellas, hoods, waterproof cloth, sheets for covering automobiles, sheets for covering building materials, and back sheets for solar batteries.    Patent Document 1: Japanese Unexamined Patent Publication No. 2003-129024